Call Admission Control Methods and Apparatus for Improving Route Selection in Packet Networks

1. Apparatus comprising: a packet switch configured for determining an equivalent bandwidth for use in a call admission control process, the equivalent bandwidth being derived from a multiplier which is a function of at least one connection parameter, wherein the multiplier is selected from a plurality of candidate multipliers, the candidate multipliers being computed and stored prior to the call admission control process.

2. The apparatus of claim 1 , wherein the packet switch is further configured for receiving a connection request including the at least one connection parameter.

3. The apparatus of claim 2 , wherein the packet switch is further configured for accessing at least one look-up table based on the at least one connection parameter to find the multiplier appropriate for the call.

4. The apparatus of claim 3 , wherein the packet switch is further configured for multiplying the appropriate multiplier by a selected bandwidth value to yield the equivalent bandwidth.

5. The apparatus of claim 4 , wherein the packet switch is further configured for comparing the equivalent bandwidth to an available bandwidth value associated with a link of a path in a network to which the packet switch is operatively coupled.

6. The apparatus of claim 5 , wherein the packet switch is further configured for setting-up the call on the path when the available bandwidth value is at least equal to the equivalent bandwidth.

7. The apparatus of claim 5 , wherein the packet switch is further configured for rejecting the call with respect to the path when the available bandwidth value is not at least equal to the equivalent bandwidth.

8. The apparatus of claim 1 , wherein the at least one connection parameter is a quality of service parameter associated with the call.

9. The apparatus of claim 1 , wherein the at least one connection parameter is a delay requirement associated with the call.

10. The apparatus of claim 9 , wherein the delay requirement is a cell delay variation requirement.

11. The apparatus of claim 1 , wherein the multiplier is also a function of a normalized bandwidth value associated with the call.

12. The apparatus of claim 1 , wherein the multiplier is also a function of at least one network parameter.

13. The apparatus of claim 1 , wherein the packet switch is further configured for use in a PNNI architecture.

14. Apparatus comprising: packet equipment configured for determining an equivalent bandwidth for use in a call admission control process, the equivalent bandwidth being derived from a multiplier which is a function of at least one connection parameter, wherein the multiplier is selected from a plurality of candidate multipliers, the candidate multipliers being computed and stored prior to the call admission control process.

15. Apparatus for performing call admission control for a requested connection in a packet network, comprising: packet equipment configured for computing a network link utilization capacity value and a probability value in response to the requested connection, the network link utilization capacity value being a function of the number of constant bit rate connections at a given link and the utilization of a constant bit rate capacity, and the probability value representing the likelihood that a delay value is less than a cell delay variation value associated with the connection, the packet equipment further configured for accepting a candidate path in the network on which to set-up the connection when the utilization capacity value is not more than a given utilization value and the probability is not more than a given likelihood value.

16. The apparatus of claim 15 , wherein the utilization capacity value is a function of the current utilization of a type of connection service on the network link.

17. The apparatus of claim 15 , wherein the utilization capacity value is a function of a capacity allocated to a type of connection service on the network link.

18. The apparatus of claim 15 , wherein the utilization capacity value is a function of an available bandwidth value on the network link.

19. The apparatus of claim 15 , wherein the probability value is a function of the number of connections of a type of connection service currently at the network link.

20. A method for use in a packet switch in a communications network, comprising the steps of: receiving a connection request; and determining an equivalent bandwidth for use in a call admission control process, the equivalent bandwidth being derived from a multiplier which is a function of at least one connection parameter, wherein the multiplier is selected from a plurality of candidate multipliers, the candidate multipliers being computed and stored prior to the cal admission control process.

21. The method of claim 20 , wherein the connection request includes the at least one connection parameter.

22. The method of claim 21 , further comprising the step of accessing at least one look-up table based on the at least one connection parameter to find the multiplier appropriate for the call.

23. The method of claim 22 , further comprising the step of multiplying the appropriate multiplier by a selected bandwidth value to yield the equivalent bandwidth.

24. The method of claim 23 , further comprising the step of comparing the equivalent bandwidth to an available bandwidth value associated with a link of a path in the network.

25. The method of claim 24 , further comprising the step of setting-up the call on the path when the available bandwidth value is at least equal to the equivalent bandwidth.

26. The method of claim 24 , further comprising the step of rejecting the call with respect to the path when the available bandwidth value is not at least equal to the equivalent bandwidth.

27. The method of claim 20 , wherein the at least one connection parameter is a quality of service parameter associated with the call.

28. The method of claim 20 , wherein the at least one connection parameter is a delay requirement associated with the call.

29. The method of claim 28 , wherein the delay requirement is a cell delay variation requirement.

30. The method of claim 20 , wherein the multiplier is also a function of a normalized bandwidth value associated with the call.

31. The method of claim 20 , wherein the multiplier is also a function of at least one network parameter.

32. The method of claim 20 , wherein the packet switch is configured for use in a PNNI architecture.

33. A method for use in packet equipment for performing call admission control for a requested connection in a packet network, comprising the steps of: computing a network link utilization capacity value and a probability value in response to the requested connection, the network link utilization capacity value being a function of the number of constant bit rate connections at a given link and the utilization of a constant bit rate capacity, and the probability value representing the likelihood that a delay value is less than a cell delay variation value associated with the connection; and accepting a candidate path in the network on which to set-up the connection when the utilization capacity value is not more than a given utilization value and the probability is not more than a given likelihood value.

34. The method of claim 33 , wherein the utilization capacity value is a function of the current utilization of a type of connection service on the network link.

35. The method of claim 33 , wherein the utilization capacity value is a function of a capacity allocated to a type of connection service on the network link.

36. The method of claim 33 , wherein the utilization capacity value is a function of an available bandwidth value on the network link.

37. The method of claim 33 , wherein the probability value is a function of the number of connections of a type of connection service currently at the network link.